Issue: July 15, 2006

Pruning honeysuckle and problems with yucca weevils

I recently retired and now have time to do things around the house. I need to prune my honeysuckle bush. When is the best time to do that? I have borers (or worms) in my yucca. What will kill them?

Dena B.

Answer:

On the Internet, you will find that most of the information is about how to kill honeysuckle (bush and vining types). In much of the country (where there is more precipitation), they think of the honeysuckle like we think of salt cedar, an invasive weed to be rid of.

Here in our drier environment, it is much less likely to become a problem, but there is a potential for it to escape into the moist river areas. Birds can spread the seed from its berries, so there is a chance for escape even in New Mexico. Please keep this in mind.

The bush honeysuckle should be pruned during its dormant season. If you remove all the previous yearŐs growth, you may lose all the spring flowers until the next year. By pruning only a few of the oldest stems each year (pruning them a few inches above ground level - rejuvenation pruning), you will be able to have flowers without a yearŐs wait.

A close relative of the agave weevil attacks yucca as well as agave plants. This insect bores in and opens the trunk to bacterial infection. The leaves begin to turn yellow and die, and a putrid smell emanates from the infected trunk. Eventually, the plant falls over and dies. The recommended treatment is to remove any yuccas that are infected. Do not leave them near any remaining uninfected yucca or agave plants. Treat the soil with insecticide labeled for control of grubs (beetle larvae). Do not replant the area with new yucca plants for 2 years to be certain that the larvae, pupae, and adults are not remaining in the soil. Before removing your yucca plants, confirm that yucca weevil is the problem by contacting your local Cooperative Extension Service office.

Plants aren't blooming

I have some Calabasas squash that arenŐt blooming. They are growing well but donŐt produce flowers. What is wrong?

Answer:

The most common reason for a plant to be growing well but not producing flowers or fruit is an excess of nitrogen fertilizer (perhaps from manure or other source) or a location that is too shady.

Nitrogen fertilizer stimulates growth of stems and leaves at the expense of flower production. Addition of phosphate fertilizer can help encourage flowering. Use a soluble phosphate source to apply with irrigation, or work the phosphate into the soil without damaging the roots of the plants.

If the garden site is too shady (not as common a problem here in New Mexico), it may not be possible to correct the problem this year. Choose a location with at least 4 to 6 hours of sunlight each day when you plant next year.

Curtis W. Smith, Ph.D., is an Extension Horticulture Specialist with New Mexico
State University's Cooperative Extension Service. New Mexico State
University is an equal opportunity/affirmative action employer and educator.